The present invention generally relates to pallets and, more particularly, to spill pallets which support liquid containing drums and are capable of retaining spilled or leaked liquid from such drums.
Spill pallets had been developed in accordance with guidelines of the United States Environmental Protection Agency (EPA) and are designed to support one or more drums to provide a reservoir to contain liquid should it escape or leak from the drums. The EPA requires that hazardous waste be stored in a containment system having a sufficient capacity to contain 10% of the volume of the containers or the volume of the largest container, whichever is greater.
A typical prior art spill pallet is disclosed in U.S. Pat. No. 5,359,955 which issued to Grebenyuk on Nov. 1, 1994. Such a spill pallet is intended to support four 55 gallon drums by having a bottom wall with a central support member extending upwardly therefrom and a series of support rails associated with a series of side walls. The central support member and the support rails provide a stable surface for one or more grates mounted thereon. Since the central support member occupies a portion of the space which would otherwise provide a containment chamber the height of the side walls must necessarily be increased to provide the required volumetric capacity of the spill pallet. It is important that the height of the spill pallet be as small as possible, since it is preferable to load drums onto the surface of the pallet by employing ramps and hand trucks rather than forklift trucks because of the possibility of puncturing adjacent drums by the forklift. However the length of the ramp incline increases proportional to the height of the pallet surface for safe hand truck operation. It is also desirable to increase the surface area of the spill pallet to gain additional volumetric capacity, but merely increasing the surface area of the prior art pallets greatly reduces the ability of the support rails to resist the additional loading.
It is also desirable to provide a pallet area in a work place having a drum supporting surface which permits the storage of a multiplicity of drums in close proximity. Prior art techniques for such a storage arrangement involve merely placing a plurality of pallets in close proximity to support the multiplicity of drums in a close packed arrangement. However since the pallets are not attached to each other, there exists the danger of one or more pallets to become shifted relative to a contiguous pallet to provide a gap or gaps between the pallets. Improper placement of a drum over such a gap will improperly load the side wall of a pallet. Furthermore merely placing a loading ramp in abutment with a side wall of a pallet will not necessarily ensure that the ramp will remain in place during the transport of a drum unto the grate surface of the pallet.